To see if the coverage bumps a little and yet still manage to complete in time

... and sorted the list alphabetically

Follow-up to 98c3f148 that removed it from the header file

Use --recursive to get boringssl in one line

Closes #4219

Closes #4217

Closes #4216

... instead of mentioning one in another place

This commit makes sending HTTP/3 request with nghttp3 work.  It
minimally receives HTTP response and calls nghttp3 callbacks, but no
processing is made at the moment.

Closes #4215

- checked for by configure
- updated docs/HTTP3.md
- shown in the version string

Closes #4210

This avoids EBADF errors from EPOLL_CTL_DEL operations in the
ephiperfifo.c example.  EBADF is dangerous in multi-threaded
applications where I rely on epoll_ctl to operate on the same
epoll description from different threads.

Follow-up to eb9a604f

Bug: https://curl.haxx.se/mail/lib-2019-08/0026.html
Closes #4211

instead of using a "greater than 0" test, check for variable being
set, as it is always set to 1, and could be left unset if non of
OPENSSL MBEDTLS GNUTLS WOLFSSL is being configured for.

Closes #4213

Closes #4212

Closes #4209

Added cloning for quiche and BoringSSL and modified the build
instructions so they work on a clean folder.

Closes #4208

There's no use for this anymore and it was never in a release.

Closes #4206

Closes #4204

Leftovers from the function rename back in 76b63489

Reported-by: Gisle Vanem
Bug: https://github.com/curl/curl/commit/f3e0f071b14fcb46a453f69bdf4e062bcaacf362#com
mitcomment-34601751

Closes #4203

So that users can mask in/out specific HTTP versions when Alt-Svc is
used.

 - Removed "h2c" and updated test case accordingly
 - Changed how the altsvc struct is laid out
 - Added ifdefs to make the unittest run even in a quiche-tree

Closes #4201

Closes #4200

RFC 7838 section 5:

   When using an alternative service, clients SHOULD include an Alt-Used
   header field in all requests.

Removed CURLALTSVC_ALTUSED again (feature is still EXPERIMENTAL thus
this is deemed ok).

You can disable sending this header just like you disable any other HTTP
header in libcurl.

Closes #4199

Even though it cannot fall-back to a lower HTTP version automatically. The
safer way to upgrade remains via CURLOPT_ALTSVC.

CURLOPT_H3 no longer has any bits that do anything and might be removed
before we remove the experimental label.

Updated the curl tool accordingly to use "--http3".

Closes #4197

Also, put the TODO items at the bottom.

Closes #4198

If a Retry-After: header was used in the response, that value overrides
other retry timing options.

Fixes #3794
Closes #4195

... instead of CURLINFO_EFFECTIVE_URL to avoid string operations.

This is only the libcurl part that provides the information. There's no
user of the parsed value. This change includes three new tests for the
parser.

Ref: #3794

Closes #4196

It can't be set for CURLOPT_HTTP_VERSION, but it can be extracted with
CURLINFO_HTTP_VERSION.